Treatment Of Carmine Dye Wastewater By Siderite And Oolitic Hematite

China's mineral resources are abundant,but some low-grade,poorly used mineral resources are restricted,and the utilization rate is low,resulting in serious waste of resources.So,processing low-grade mineral resources into environmental engineering materials is an important research direction.In this paper,siderite and oolitic hematite were characterized and analyzed using X-ray diffraction?XRD?,X-ray fluorescence?XRF?,Transmission electron microscopy?TEM?,Fourier infrared spectroscopy?FITR?,and X-ray photoelectron spectroscopy?XPS?.Based on the characterization analysis,the performance of low-grade siderite as a solid iron source in the Fenton-like reaction,and the performance of hydrogen-reduced oolitic hematite in the treatment of carmine dye wastewater mechanism of action.In the experiment of siderite catalyzed hydrogen peroxide to degrade carmine dye,the role of siderite and the removal mechanism of reaction were investigated.The effects of the size of the siderite,the ratio of H₂O₂ and Fe²⁺,the initial pH value,the reaction time and the reaction temperature on the degradation were investigated.And the degradation mechanism and reaction kinetics were discussed.The results showed that in the H₂O₂/siderite system,the particle size of the siderite had little effect on the degradation.At pH=3,H₂O₂/Fe²⁺=6,the decolorization efficiency was 99.97%,the TOC removal efficiency was 80.61%,the reaction order was 1.04,and the rate constant was10.15 min^-1.The results showed that siderite can continuously release the catalyst Fe²⁺under hot acidic conditions in the H₂O₂/siderite system.The carmine was degraded under the same conditions with the siderite cycle for 8 times,and the decolorization efficiency was hardly affected,and both of them could reach 99%or more.It illustrated the recyclability of siderite in wastewater treatment processes and its potential for environmental management.Zero-valent iron?ZVI?prepared by reduction of oolitic hematite by hydrogen is used to degrade carmine dye wastewater and characterize the microstructure characteristics of the sample before and after reaction.The influencing factors of ZVI degradation carmine dye wastewater were investigated,including solution pH,solid-liquid ratio,reaction time and temperature.The pH and intermediates of the aqueous solution were monitored before and after the reaction.The purification mechanism was discussed based on the comprehensive analysis of various methods.The results showed that when the pH value was 2.0,the solid-liquid ratio was 1g/L,the decolorization efficiency can reach 98.9%when the reaction time was 1.5h.The TOC removal efficiency can reach57%was when the reaction time was 24h.The degradation of chroma by ZVI is consistent with the first-order reaction kinetics and the second-order reaction kinetics.Meanwhile,the degradation of TOC in carmine by ZVI accords with Freundlich and pseudo-second order kinetics.The experimental results showed that the method for preparing ZVI is feasible,and the prepared ZVI can be used for the treatment of printing and dyeing wastewater.